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Thomas Daldrup - One of the best experts on this subject based on the ideXlab platform.

  • A sensitive method for the determination of Hordenine in human serum by ESI^+ UPLC-MS/MS for forensic toxicological applications
    Analytical and Bioanalytical Chemistry, 2016
    Co-Authors: Irina Steiner, Gernot Brauers, Oliver Temme, Thomas Daldrup
    Abstract:

    We present the determination of the alkaloid Hordenine and its forensic relevance as a qualitative and quantitative marker for beer consumption. A simple, rapid and sensitive ultra-performance liquid chromatography (UPLC)–tandem mass spectrometry (MS/MS) method for the determination of Hordenine in human serum samples was developed and validated. The application was tested with serum samples after enzymatic cleavage. After addition of the synthesized internal standard Hordenine- D _4, a liquid–liquid extraction with dichloromethane and diethyl ether was performed. Chromatographic separation was conducted with a Waters Acquity® UPLC system with gradient elution on an Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm, 5-μm particle size). For quantification, a Waters Acquity® TQ detector (version SNC 627) with a positive electrospray ionization probe and multiple reaction monitoring mode was used. A flow rate of 0.4 ml/min was applied. The retention time for both the analyte and the internal standard was 3.67 min. Linearity was demonstrated from 0.2 to 16 ng/ml ( R ^2 > 0.999). The lower limit of quantification was 0.3 ng/ml in serum. Matrix effects and extraction recoveries for low and high concentrations were within acceptable limits of 75–125 % and 50 %, respectively. To the best of our knowledge there is no corresponding method for the determination of Hordenine by UPLC–MS/MS in serum. By our drinking studies we demonstrate that beer consumption leads to detectable Hordenine concentrations in serum and observed a linear elimination of total Hordenine correlating to blood alcohol concentration, which shows that Hordenine can be used as a reliable qualitative and quantitative marker for beer consumption. The validated method was successfully applied to serum from actual forensic cases. Graphical Abstract Determination of Hordenine in human serum samples by ESI^+ UPLC-MS/MS

  • A sensitive method for the determination of Hordenine in human serum by ESI+ UPLC-MS/MS for forensic toxicological applications
    Analytical and Bioanalytical Chemistry, 2016
    Co-Authors: Irina Steiner, Gernot Brauers, Oliver Temme, Thomas Daldrup
    Abstract:

    We present the determination of the alkaloid Hordenine and its forensic relevance as a qualitative and quantitative marker for beer consumption. A simple, rapid and sensitive ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS) method for the determination of Hordenine in human serum samples was developed and validated. The application was tested with serum samples after enzymatic cleavage. After addition of the synthesized internal standard Hordenine-D 4, a liquid-liquid extraction with dichloromethane and diethyl ether was performed. Chromatographic separation was conducted with a Waters Acquity® UPLC system with gradient elution on an Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm, 5-μm particle size). For quantification, a Waters Acquity® TQ detector (version SNC 627) with a positive electrospray ionization probe and multiple reaction monitoring mode was used. A flow rate of 0.4 ml/min was applied. The retention time for both the analyte and the internal standard was 3.67 min. Linearity was demonstrated from 0.2 to 16 ng/ml (R(2) > 0.999). The lower limit of quantification was 0.3 ng/ml in serum. Matrix effects and extraction recoveries for low and high concentrations were within acceptable limits of 75-125% and 50%, respectively. To the best of our knowledge there is no corresponding method for the determination of Hordenine by UPLC-MS/MS in serum. By our drinking studies we demonstrate that beer consumption leads to detectable Hordenine concentrations in serum and observed a linear elimination of total Hordenine correlating to blood alcohol concentration, which shows that Hordenine can be used as a reliable qualitative and quantitative marker for beer consumption. The validated method was successfully applied to serum from actual forensic cases.

Jv Lovett - One of the best experts on this subject based on the ideXlab platform.

Irina Steiner - One of the best experts on this subject based on the ideXlab platform.

  • A sensitive method for the determination of Hordenine in human serum by ESI^+ UPLC-MS/MS for forensic toxicological applications
    Analytical and Bioanalytical Chemistry, 2016
    Co-Authors: Irina Steiner, Gernot Brauers, Oliver Temme, Thomas Daldrup
    Abstract:

    We present the determination of the alkaloid Hordenine and its forensic relevance as a qualitative and quantitative marker for beer consumption. A simple, rapid and sensitive ultra-performance liquid chromatography (UPLC)–tandem mass spectrometry (MS/MS) method for the determination of Hordenine in human serum samples was developed and validated. The application was tested with serum samples after enzymatic cleavage. After addition of the synthesized internal standard Hordenine- D _4, a liquid–liquid extraction with dichloromethane and diethyl ether was performed. Chromatographic separation was conducted with a Waters Acquity® UPLC system with gradient elution on an Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm, 5-μm particle size). For quantification, a Waters Acquity® TQ detector (version SNC 627) with a positive electrospray ionization probe and multiple reaction monitoring mode was used. A flow rate of 0.4 ml/min was applied. The retention time for both the analyte and the internal standard was 3.67 min. Linearity was demonstrated from 0.2 to 16 ng/ml ( R ^2 > 0.999). The lower limit of quantification was 0.3 ng/ml in serum. Matrix effects and extraction recoveries for low and high concentrations were within acceptable limits of 75–125 % and 50 %, respectively. To the best of our knowledge there is no corresponding method for the determination of Hordenine by UPLC–MS/MS in serum. By our drinking studies we demonstrate that beer consumption leads to detectable Hordenine concentrations in serum and observed a linear elimination of total Hordenine correlating to blood alcohol concentration, which shows that Hordenine can be used as a reliable qualitative and quantitative marker for beer consumption. The validated method was successfully applied to serum from actual forensic cases. Graphical Abstract Determination of Hordenine in human serum samples by ESI^+ UPLC-MS/MS

  • A sensitive method for the determination of Hordenine in human serum by ESI+ UPLC-MS/MS for forensic toxicological applications
    Analytical and Bioanalytical Chemistry, 2016
    Co-Authors: Irina Steiner, Gernot Brauers, Oliver Temme, Thomas Daldrup
    Abstract:

    We present the determination of the alkaloid Hordenine and its forensic relevance as a qualitative and quantitative marker for beer consumption. A simple, rapid and sensitive ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS) method for the determination of Hordenine in human serum samples was developed and validated. The application was tested with serum samples after enzymatic cleavage. After addition of the synthesized internal standard Hordenine-D 4, a liquid-liquid extraction with dichloromethane and diethyl ether was performed. Chromatographic separation was conducted with a Waters Acquity® UPLC system with gradient elution on an Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm, 5-μm particle size). For quantification, a Waters Acquity® TQ detector (version SNC 627) with a positive electrospray ionization probe and multiple reaction monitoring mode was used. A flow rate of 0.4 ml/min was applied. The retention time for both the analyte and the internal standard was 3.67 min. Linearity was demonstrated from 0.2 to 16 ng/ml (R(2) > 0.999). The lower limit of quantification was 0.3 ng/ml in serum. Matrix effects and extraction recoveries for low and high concentrations were within acceptable limits of 75-125% and 50%, respectively. To the best of our knowledge there is no corresponding method for the determination of Hordenine by UPLC-MS/MS in serum. By our drinking studies we demonstrate that beer consumption leads to detectable Hordenine concentrations in serum and observed a linear elimination of total Hordenine correlating to blood alcohol concentration, which shows that Hordenine can be used as a reliable qualitative and quantitative marker for beer consumption. The validated method was successfully applied to serum from actual forensic cases.

Xianqin Wang - One of the best experts on this subject based on the ideXlab platform.

  • validated uplc ms ms method for determination of Hordenine in rat plasma and its application to pharmacokinetic study
    Journal of Pharmaceutical and Biomedical Analysis, 2015
    Co-Authors: Shuanghu Wang, Xueli Huang, Peiwu Geng, Congcong Wen, Yunfang Zhou, Xianqin Wang
    Abstract:

    Abstract Hordenine is an active compound found in several foods, herbs and beer. In this work, a sensitive and selective UPLC–MS/MS method for determination of Hordenine in rat plasma was developed. After addition of caulophylline as internal standard (IS), protein precipitation by acetonitrile–methanol (9:1, v/v) was used as sample preparation. Chromatographic separation was achieved on a UPLC BEH HILIC (2.1 mm × 100 mm, 1.7 μm) with acetonitrile (containing 10 mM ammonium formate) and water (containing 0.1% formic acid and 10 mM ammonium formate) as mobile phase with gradient elution. An electrospray ionization source was applied and operated in positive ion mode; multiple reaction monitoring (MRM) mode was used for quantification using target fragment ions m / z 166.1 → 121.0 for Hordenine and m / z 205.1 → 58.0 for IS. Calibration plots were linear over the range of 2–2000 ng/mL for Hordenine in rat plasma. Mean recoveries of Hordenine in rat plasma were in the range of 80.4–87.3%. RSD of intra-day and inter-day precision were both

  • Validated UPLC–MS/MS method for determination of Hordenine in rat plasma and its application to pharmacokinetic study
    Journal of Pharmaceutical and Biomedical Analysis, 2015
    Co-Authors: Shuanghu Wang, Xueli Huang, Peiwu Geng, Congcong Wen, Yunfang Zhou, Xianqin Wang
    Abstract:

    Abstract Hordenine is an active compound found in several foods, herbs and beer. In this work, a sensitive and selective UPLC–MS/MS method for determination of Hordenine in rat plasma was developed. After addition of caulophylline as internal standard (IS), protein precipitation by acetonitrile–methanol (9:1, v/v) was used as sample preparation. Chromatographic separation was achieved on a UPLC BEH HILIC (2.1 mm × 100 mm, 1.7 μm) with acetonitrile (containing 10 mM ammonium formate) and water (containing 0.1% formic acid and 10 mM ammonium formate) as mobile phase with gradient elution. An electrospray ionization source was applied and operated in positive ion mode; multiple reaction monitoring (MRM) mode was used for quantification using target fragment ions m / z 166.1 → 121.0 for Hordenine and m / z 205.1 → 58.0 for IS. Calibration plots were linear over the range of 2–2000 ng/mL for Hordenine in rat plasma. Mean recoveries of Hordenine in rat plasma were in the range of 80.4–87.3%. RSD of intra-day and inter-day precision were both

Ai-qun Jia - One of the best experts on this subject based on the ideXlab platform.

  • Metabolomic analysis of quorum sensing inhibitor Hordenine on Pseudomonas aeruginosa.
    Applied Microbiology and Biotechnology, 2019
    Co-Authors: Jin-wei Zhou, Bing Sun, Jun-song Wang, Junaid Muhammad, Rui Yang, Abdul Wadood, Ai-qun Jia
    Abstract:

    Proton magnetic resonance–based metabolomics analysis was performed to determine the global metabolite changes in pathogenic bacterium Pseudomonas aeruginosa PAO1 following exposure to quorum sensing (QS) inhibitor Hordenine. Pyocyanin inhibition assay confirmed that Hordenine exhibited potent QS inhibitory activity. A total of 40 metabolites were assigned by PMR spectra. Hordenine treatment resulted in the destruction of QS system in P. aeruginosa PAO1 by downregulating the expressions of genes involved in QS. The synthesis of antioxidant enzymes was repressed and the oxidative stress was enhanced due to the dysfunctional QS system of P. aeruginosa PAO1. The enhanced oxidative stress induced by the dysfunctional QS system of P. aeruginosa PAO1 altered the membrane components, enhanced membrane permeability, and disturbed energy metabolism, amino acid metabolism, and nucleotide metabolism, and would ultimately attenuate the pathogenicity of P. aeruginosa PAO1. Hordenine may have promising potential for controlling nosocomial pathogens.

  • Inhibition of Quorum Sensing and Virulence in Serratia marcescens by Hordenine.
    Journal of Agricultural and Food Chemistry, 2019
    Co-Authors: Jin-wei Zhou, Huan Jiang, Ling-yu Ruan, Hongjuan Chen, Huai-zhi Luo, Jun-song Wang, Ai-qun Jia
    Abstract:

    Serratia marcescens NJ01 is a pathogenic bacterium isolated from diseased tomato leaves. Here, we report on the development of a tomato- S. marcescens host-pathogen system as a model to evaluate the effects of Hordenine on quorum sensing (QS)-mediated pathogenicity under native conditions. Exposure to Hordenine at 25, 50, and 100 μg/mL significantly inhibited the production of acyl-homoserine lactones and the formation of biofilms. Hordenine treatment notably enhanced the susceptibility of the preformed biofilms to ciprofloxacin by reducing the production of extracellular polysaccharides, destroying the architecture of biofilms, and changing the permeability of membranes, as evidenced by the scattered appearance and dominant red fluorescence in the combination-treated biofilms. Furthermore, the addition of Hordenine affected the production of virulence factors, influenced the intracellular metabolites, and downregulated the expressions of QS- and biofilm-related genes. The plant infection model indicated that Hordenine could significantly attenuate the pathogenicity of S. marcescens NJ01 in tomato plants. Thus, Hordenine could act as a potential pesticide or pesticide accelerant in treating crop infections.

  • Inhibition of Quorum Sensing and Virulence in Serratia marcescens by Hordenine
    2019
    Co-Authors: Jin-wei Zhou, Huan Jiang, Ling-yu Ruan, Hongjuan Chen, Huai-zhi Luo, Jun-song Wang, Ai-qun Jia
    Abstract:

    Serratia marcescens NJ01 is a pathogenic bacterium isolated from diseased tomato leaves. Here, we report on the development of a tomato–S. marcescens host–pathogen system as a model to evaluate the effects of Hordenine on quorum sensing (QS)-mediated pathogenicity under native conditions. Exposure to Hordenine at 25, 50, and 100 μg/mL significantly inhibited the production of acyl-homoserine lactones and the formation of biofilms. Hordenine treatment notably enhanced the susceptibility of the preformed biofilms to ciprofloxacin by reducing the production of extracellular polysaccharides, destroying the architecture of biofilms, and changing the permeability of membranes, as evidenced by the scattered appearance and dominant red fluorescence in the combination-treated biofilms. Furthermore, the addition of Hordenine affected the production of virulence factors, influenced the intracellular metabolites, and downregulated the expressions of QS- and biofilm-related genes. The plant infection model indicated that Hordenine could significantly attenuate the pathogenicity of S. marcescens NJ01 in tomato plants. Thus, Hordenine could act as a potential pesticide or pesticide accelerant in treating crop infections

  • Attenuation of Pseudomonas aeruginosa biofilm by Hordenine: a combinatorial study with aminoglycoside antibiotics
    Applied Microbiology and Biotechnology, 2018
    Co-Authors: Jin-wei Zhou, Bo Hou, Gen-yan Liu, Huan Jiang, Bing Sun, Zhen-nan Wang, Ruo-fu Shi, Rong Wang, Ai-qun Jia
    Abstract:

    Pseudomonas aeruginosa is a ubiquitous pathogen that is the leading cause of chronic infections. Bacterial biofilm formation facilitates CF development and restricts the anti-bacterial potential of many current antibiotics. The capacity of P. aeruginosa to form biofilms and resist antibiotics is closely correlated with quorum sensing (QS). Disrupting QS by QS inhibitors is a promising strategy for treating chronic infections. Here, we evaluated the effect of Hordenine, a recently characterized QS inhibitor, on the susceptibility of aminoglycoside antibiotics against P. aeruginosa biofilms. Hordenine significantly enhanced the susceptibility of aminoglycoside antibiotics tobramycin, gentamycin, and amikacin against P. aeruginosa PAO1 biofilm formation. Combinations of Hordenine and aminoglycoside antibiotics showed potent efficiency in disrupting the preformed biofilms of P. aeruginosa. Microscopic observations showed flat, scattered, and unstructured biofilm architecture after treatment with Hordenine. Mechanistic study further revealed that Hordenine treatment led to the downregulation of genes involved in QS and biofilm formation. Thus, our results suggest that Hordenine has the potential to function as an antibiotic accelerant in treating P. aeruginosa infections.

  • Hordenine: A Novel Quorum Sensing Inhibitor and Antibiofilm Agent against Pseudomonas aeruginosa.
    Journal of Agricultural and Food Chemistry, 2018
    Co-Authors: Jin-wei Zhou, Huan Jiang, Huai-zhi Luo, Ting-kun Jian, Zi-qian Chen, Ai-qun Jia
    Abstract:

    The quorum sensing (QS) inhibitory activity of Hordenine from sprouting barley against foodborne pathogen Pseudomonas aeruginosa was evaluated for the first time here. At concentrations ranging from 0.5 to 1.0 mg mL–1, Hordenine inhibited the levels of acyl-homoserine lactones. The enhanced susceptibility of Hordenine with netilmicin on P. aeruginosa PAO1 biofilm formation as well as their efficiency in disrupting preformed biofilms was also evaluated using scanning electron microscopy and confocal laser scanning microscopy (CLSM). Hordenine treatment inhibited the production of QS-related extracellular virulence factors of P. aeruginosa PAO1. Additionally, quantitative real-time polymerase chain reaction analysis demonstrated that the expressions of QS-related genes, lasI, lasR, rhlI, and rhlR, were significantly suppressed. Our results indicated that Hordenine can serve as a competitive inhibitor for signaling molecules and act as a novel QS-based agent to defend against foodborne pathogens.